


Dirty Little Secrets

by lionheart (cruel_oath)



Series: Tumblr Requests 2018 [1]
Category: Final Fantasy XV
Genre: Anal Sex, Canon Divergence - No War, Face Slapping, Face-Sitting, Multi, Oral Sex, Role Reversal, Tumblr request, Vaginal Sex, sexual fantasies
Language: English
Status: Completed
Published: 2018-01-16
Updated: 2018-01-16
Packaged: 2019-03-05 13:45:35
Rating: Explicit
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 2,729
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/13389063
Author URL: https://archiveofourown.org/users/cruel_oath/pseuds/lionheart
Summary: Lately, Noctis has been spending a lot of time thinking about his best friend and his fiancée.[Tumblr request - promnoctluna + role reversal]





	Dirty Little Secrets

**Author's Note:**

> I received this request late last year and it took me two months to do it, but it's finally done! Thank you so much for being so patient, anon.

Shortly after the war ended, Luna came to Lucis to visit Noctis in person after _years_ of writing letters in a notebook. This meant that Noctis’ friends got to meet her for the first time, and none of there were quite as excited as Prompto.

As expected, Prompto and Luna hit it off really well. They had immediately bonded over Luna’s dogs and Prompto’s photographs, and by the end of her visit, they were as close as they could be. Before she left, she gave him a little blue notebook, and gave him the same set of instructions she had given Noctis all those years ago― _"I want you to put something in this book and send it back.”_

Looking back on it, this is probably where it all started.

Noctis’ fantasies started out innocent enough―sharing soft kisses with Prompto and Luna, trying to cram into a photobooth at the mall, and falling asleep together in Noctis’ king-sized bed. He finds himself daydreaming during council meetings, wishing that he could be snuggled up on the couch with Prompto and Luna, watching some stupid rom-com and laughing about how utterly ridiculous it was. His dreams were filled with romantic dates, which he details in a journal he keeps hidden under his bed.

After Luna and Noctis get engaged, his thoughts become a little more… _exciting._

Noctis’ internet went out in his apartment during a storm that struck Lucis. Prompto was spending time with his family for the first time in _months,_ so Noctis decides not to bother him. His only means of speaking to Luna is a notebook, so that left him with little to do.

Noctis tries to find something to do—read reports, play video games, _something_ other than just sitting there, but he can’t stop thinking about the three of them together. Specifically, he can’t stop thinking about his best friend fucking his fiancée.

Noctis closes his eyes, palming himself through his sweatpants. He imagines Prompto and Luna making out on the couch beside him, their hands roaming. Clothes are dropped to the floor and Prompto’s kissing down Luna’s body until his head is between her legs. Noctis pushes his sweats and boxers down to expose his cock when he pictures Prompto eating Luna out, making her scream with pleasure.

In the back of his mind, he thinks Prompto would give good head.

Noctis’ thumb swirls over his slit, a moan tearing out of his throat. He sees Prompto’s tongue pressing against Luna’s clit mercilessly, his fingers slipping into her effortlessly. Luna has her finger tangled up in Prompto’s hair, swearing and gasping and chanting, “I’m gonna cum, I’m gonna cum, I’m gonna cum!”

Prompto doesn’t let up until well after her first orgasm, after which Luna pulls him in for a rough, needy kiss. Her tongue runs across his lips, tasting herself and letting out a soft moan when Prompto’s fingers find their way back inside her. Noctis lets out a choked moan, giving himself a few sharp tugs.

_“Enjoying the show?”_

Prompto doesn’t look away from Luna, but Noctis knows it’s directed towards him.

“Fuck, _yes.”_

_“Then maybe you should join us, darling.”_

Noctis wants to— _Astrals, he wants to_ —but his orgasm hits before it goes any further. He opens his eyes, finding himself alone on the couch.

* * *

 

Noctis notices he has it bad when he starts recording his fantasies into a journal. He picks out one that looks identical to the one he communicates to Luna with, knowing Ignis won’t snoop out of respect for her.

He revisits them when Prompto and Ignis go home for the night. He’d pick one based on how stressful his day had been and let himself get immersed, going as far as to purchase a few toys to help get him off.

Tonight, he’s on his knees in front of the fucking machine he invested in a little while back. As it thrusts into him, he closes his eyes, pretending that it’s Prompto instead.

Luna’s watching them, her legs spread and her fingers buried inside her, watching Prompto fuck Noctis into the sheets. She’s as composed as ever, in spite of the scene in front of her.

 _“Prompto, darling,”_ Luna says, her voice as sweet as honey, _“I do think he can take more than that.”_

_“Couldn’t agree more.”_

Noctis’ hand reaches for the switchboard. He turns up the machine, moaning when the dildo pounds into his prostate.

“Fuck,” Noctis swears, _“Prompto…”_

Noctis’ hand wraps around his cock. He pretends it’s Prompto stroking him, begging for Luna to let him cum.

_“You think he’s earned it, Lady Luna?”_

Luna pauses, letting a moan slip out. _“A little longer, perhaps.”_

Noctis whimpers, pressing against the machine. “Please, Luna, _fuck!”_

Luna doesn’t offer him a reply. She pulls Prompto down for a kiss, tweaking one of his nipples. Prompto groans against her lips, but his thrusts don’t falter. His cock pounds against Noctis’ prostate until he’s a sobbing wreck, begging and pleading for Luna to let him cum.

 _“Go on,”_ Luna says, _“Show Prompto how good he makes you feel.”_

When Noctis cums, he sees stars. It takes all his remaining energy to pull off the fucking machine and put it away. He collapses on his bed, not even bothering to get clean sheets. Noctis falls asleep, wishing he was snuggled up between Luna and Prompto.

* * *

 

When Luna returns to Insomnia, there’s about two months before the wedding.

Noctis takes her and Prompto out to lunch to catch up. It’s nice—they talk about the wedding, Prompto shows Luna some of his new photographs, and they just focus on having a good time. After lunch, Prompto has to leave for training. Noctis and Luna go back to his apartment to spend some time alone before they’re bombarded with their respective duties.

“Oh!” When they enter the apartment, Luna spots their journal on the coffee table. She smiles, picking it up. “It seems like just yesterday, I received your first message. It’s difficult to believe it’s been so long.”

Noctis smiles, albeit confused. He doesn’t keep _their_ journal out like that, so how did it end up out here?

He takes a closer look at the journal, finding a small, somewhat noticeable stain on the back cover. His eyes go wide when he remembers his activities earlier in the day.

“Wait!” Noctis snatches the journal out of her hands, earning a hurt look.

“Noctis,” Luna says, “is there something wrong?”

“No, no, no! Everything’s fine!” Noctis gives Luna a sheepish smile, silently begging for a change of subject.

Unfortunately, Luna doesn’t relent. “Noctis, we’ve both seen what’s in the journal. I don’t see what the problem is with reminiscing.”

“There’s nothing wrong with that! I just… um, I…”

Luna gently takes the journal from him. She opens it, letting out a sigh. “Noctis, darling, if you’re _embarrassed_ about what you wrote as a _child,_ I’m sure I’ve written things that were… just as… oh.”

Noctis expects Luna to cry or scream or call off the wedding. He expects her to storm out of his apartment and tell his father, but she doesn’t do any of that. Instead, she puts the journal down and takes Noctis’ hand in her own.

“Noctis,” Luna says, her tone gentle, “look at me, darling.”

Noctis wants to fucking _cry_ from shame, but he obeys. Luna cups his cheek, offering him a sincere smile.

“How long?”

Noctis fights the urge to look away. “Since the first time you came to Insomnia.”

Luna lets out a soft laugh. “I admit, I’m _surprised,_ but I’m not angry. Actually… quite the opposite.”

Noctis raises an eyebrow. “You mean..?”

“I’ve had my fair share of fantasies about you and Prompto,” Luna says. “I didn’t plan on _acting_ on my feelings, of course, but… perhaps we should discuss this with him.”

Noctis should probably say no―he’s sure Luna would agree that their friendship with Prompto is more important than getting off―but he shoots him a text telling him to come by after training, anyway.

When Prompto shows up an hour later, Noctis almost backpedals. He stalls until Luna decides to step in, giving Noctis a look that screams _now or never._

“We actually had something very important to discuss with you, Prompto. Right, Noctis?”

“Yeah, um…” Noctis scratches the back of his head. He tries to remember the discussion he and Luna had before Prompto arrived, but he just can’t think straight.

“Noct..?” Prompto sounds… _scared,_ like he thinks Noctis might outright dump him.

Noctis wants to smack himself. _Nice going, Prince Charmless._ “Prompto, um…”

“Maybe I should go―”

Noctis moves before he even has a chance to think about his actions. He pulls Prompto forward, their lips crashing together. Prompto makes a noise caught between surprise and panic, which is enough to make Noctis pull away.

“N-Noct! What―but, Luna― _you’re supposed to―”_ Prompto gives Luna a bewildered look, which morphs into _confused_ when he sees that she’s _smiling._

“Well, that certainly isn’t what I had in mind, but I suppose it’ll do.” Luna moves to sit next to Prompto, pressing a soft kiss to his lips. “Noctis and I have grown quite fond of you.”

Prompto blinks. “I must be dreaming.”

Noctis pinches Prompto’s arm, earning a sharp hiss. Thankfully, it’s enough to break the tension, though he does earn a light punch to the shoulder from Luna.

“You most certainly aren’t dreaming, Prompto,” Luna says. “I do apologize for our lack of tact, though. It seems _somebody_ forgot the talk we had before you arrived.”

“I panicked!” Noctis says. “But, um… yeah. Sorry.”

“We certainly don’t blame you if you don’t feel the same―”

“Actually, um… I never said I wasn’t interested,” Prompto says, his voice quiet. “Um… we sure this isn’t a dream?”

“Do I need to pinch you again?”

“It’s a little early in our relationship to be getting kinky, don’t you― _ow!”_

* * *

 

It takes Noctis three months to let Prompto read the journal.

It’s so _embarrassing,_ Noctis can’t bring himself to look Prompto in the eye for a few days. He doesn’t really get over it until he comes home one night and finds that Luna’s not in her usual place on the couch, reading one of Prompto’s science fiction novels.

Noctis thinks he’s alone until he hears something coming from their room. He summons his blade, just in case it happens to be an intruder―

“Oh, _fuck,_ Prompto!”

Noctis freezes, dismissing his weapon. He then notices that the door is open, just enough for him to peek through.

He’s got the perfect view of Luna on the bed, her legs spread and her head thrown back. Prompto’s kneeling down in front of her, his head between her legs and a hand resting on her thigh.

Noctis feels his trousers get uncomfortably tight.

“Prom, _Prom,_ I’m going to cum,” Luna gasps, tangling her fingers into Prompto’s hair. “Oh, _Astrals!”_

Prompto doesn’t let up. His hand moves away from her thigh and disappears from Noctis’ sight, but going by the string of swears that spill from Luna’s mouth, he can take a guess as to where it went.

By the time Luna climaxes, Noctis can’t ignore his cock any longer. He goes to unzip his trousers, but he stops dead in his tracks when he hears Prompto’s voice.

“Enjoying the show?”

Noctis can’t bring himself to move, he’s so shocked by the fact that he’s been caught red-handed. He snaps back to reality when he’s dragged into the room and thrown onto the bed, his partners leering.

“I’ll take that as a yes,” Prompto purrs, his hand brushing against Noctis’ bulge. He whines at the contact, pressing against his palm.

“You liked seeing me eat your queen out, didn’t you?” Prompto asks.

Noctis groans, nodding. “Fuck, Prom―”

Prompto _slaps_ him. He’s aware of his stinging cheek, but all he can focus on is how _hot_ that was.

“She’s my queen now,” Prompto says, straddling Noctis’ hips. He grinds down on him slowly, earning a soft, shaky moan. “So what does that make me?”

It takes Noctis several moments and another slap to the face to get his mouth to cooperate. “My king.”

“Atta boy.” Prompto slips off Noctis’ tie, using it to bind his wrists to the headboard. He begins to unbutton his dress shirt while Luna rids Noctis of his belt and trousers. His shirt and boxers join the rest of his clothes, leaving him naked.

Noctis watches Luna reach for something on the nightstand―a bottle of lube and two condoms. She hands one to Prompto and rips the other one open, rolling it onto Noctis’ cock and slicking him up.

“Maybe next time we should do this in the throne room,” Luna says, straddling Noctis hips. She lowers herself onto him, taking him in slowly. “ _Six,_ I wouldn’t mind tying him to my throne.”

“He’d be a nice addition to your throne,” Prompto says from behind her. Noctis can’t see what he’s doing, but he can feel his finger against his entrance, slick with lube.

Luna begins to move, but between that and Prompto finger-fucking him, Noctis is a little overwhelmed. His eyes slide shut for a moment, swearing under his breath when Luna began to move faster.

“Astrals, _please,”_ Noctis whines. He feels Prompto add another finger. “Your Majesty…”

Luna pinches one of Noctis’ nipples between her fingers, twisting lightly. “Hush, now. His Majesty doesn’t reward the impatient.”

Time seems to slow down―it takes an eternity for Prompto to add a third finger, and even longer to finish preparing him. It wasn’t until Luna had her second orgasm that Noctis realized that Prompto had removed his fingers.

Luna pulls off of Noctis, her thighs shaking the slightest bit. Prompto pulls her in for a kiss, this fingers rubbing her clit hard. It doesn’t take too long to work her back up, and by the time they pull apart, Noctis is sure she’s about ready to cum again.

Noctis watches Prompto slick up his cock, a moan of anticipation escaping him. Prompto smirks, lining himself up and slowly pushing into him.

Noctis swears, throwing his head back. He’d gotten off on the thought of getting fucked by Prompto plenty of times before, but _actually_ experiencing it completely shattered his expectations.

“Oh, _fuck,”_ Noctis gasps.

Luna straddles his chest, her gaze clouded with lust. “His Majesty set the bar high,” she says, “I do hope you can meet my expectations.”

Luna moves up, leaning against the headboard for support. She lowers herself onto Noctis, letting out a soft gasp when his tongue brushed against her clit. “O-oh, _Astrals.”_

Noctis pushes his tongue into her, matching Prompto’s thrusts. She leaning on the headboard heavily now, her thighs shaking with the effort it’s taking to stay up. He hears a warning before Luna cums with a cry, gripping the headboard until her knuckles turn white.

Luna pulls off of him, crawling to the other end of the bed. She pulls Prompto in for another kiss, rough and needy. Prompto moans against her lips, his thrusts faltering enough for Noctis to know he’s getting close, too.

Luna’s hand wraps around Noctis’ cock, stroking him until he climaxes. He clenches around Prompto, sending him over the edge.

“Six.” Noctis feels Prompto pull out of him slowly. “You alright, Noct?”

“Better than alright,” Noctis says. He feels Luna untie his wrists, her hands gently massaging the ache out of them. “Didn’t think you had it in you to be so dominant.”

“Neither did I,” Prompto says, letting out a sheepish laugh as he began to clean up.

“I thought he was going to have a panic attack when I told him this was the entry I wanted to recreate,” Luna says. She presses a kiss to both of Noctis’ wrists before setting them down.

“You did great,” Noctis assures.

“Good to hear.” Prompto lets out a relieved sigh as he finishes cleaning up. “You need anything? Either of you?”

“A nap,” Noctis says.

Prompto lets out a soft laugh, climbing onto the bed. He and Luna help Noctis under the covers before settling down on either side of him. Luna begins to sing some Tenebraen lullaby that Noctis vaguely remembers, and as he drifts off, he wonders why he didn’t act on his feelings sooner.


End file.
